FR2648343A1 - Heat-insulating sheet for medical and surgical use - Google Patents

Abstract

The heat-insulating sheet 1 comprises at least one heat-reflecting layer 2 and at least one heat-insulating layer 3, 4 fixed to the abovementioned heat-reflecting layer 2, one 3 of the heat-insulating layers being coated with a sheet of fabric 5 whose outer face is designed to afford a non-slip effect. Application in cardiovascular surgery, thermotherapy or cryotherapy.

Description

 The present invention is not related to the field of medical accessories. The subject of this invention is in particular a thermally insulating composite sheet intended for effective protection against the cold in general, or of cooled parts which must not be heated, or else of prolonging or maintaining the cooling or the heating of a limb or of 'an organ in particular of human type.

The invention therefore relates to said sheet thermally
insulator as well as several applications thereof, in particular an application to the production of a phrenic nerve protective device, which is intended to be used in cardiovascular surgery (in particular open heart surgery).

In orthopedics, medicine or surgery, we use, to maintain or maintain the temperature of the human body or an organ, cloths or not
woven. These materials do not provide very effective thermal insolation and, in addition, on contact with a liquid or blood, even completely lose their insulating power.

The object of the present invention is to provide a thermally insulating sheet which does not have the
disadvantages of known devices.

 The applications of the present invention are multiple.

For example, it can be used in the do ma ine of heating or cooling dressings in order to prolong their heating or cooling action, to
thermal insulation of cushions or mattresses of water or gel to avoid the unpleasant feeling of cooling of the parts of the body in contact with them. in the operating room, in the form of a sheet or glove to avoid or delay the reheating of the heart which is permanently chilled or for the protection of the phrenic nerve which must not be cooled by the heart.

 The thermally insulating sheet according to the invention is particularly advantageous in that it has a composite structure which allows it to perform two complementary actions: double thermal insulation and thermal reflection reinforcing the power insulation of the insulating elements of the sheet. Using the sheet according to the invention, it is possible to create a thermal barrier between a region or a hot organ and a region or a cold organ.

 For there to be reflection of the human body's own heat, it is necessary to provide an air space between this human body and the thermally reflective layer of the sheet according to the invention. On the other hand. in order to conserve the heat of the reflective middle layer, it is necessary that the region of the sheet, opposite to the human body, is also thermally insulating so that said central layer does not lose calories by thermal conductivity.

 The thermally insulating sheet according to the invention is thus characterized in that it comprises at least one thermally insulating layer and at least one thermally insulating layer fixed to the aforementioned thermally reflecting layer.

 According to a first variant embodiment, the insulating sheet 1 comprises more than one reflecting layer and several thermally insulating layers, each thermally reflecting layer being between two adjacent thermally insulating layers.

 Preferably, one layer of the outer insulating layers is coated with a sheet of fabric and the outer face of this sheet of fabric is shaped to provide a non-slip effect.

 More preferably, each thermally reflective layer comprises a sheet of vacuum metallized polyester, an aluminum sheet, or an aluminum paint or varnish.

 According to the invention, each thermally insulating layer comprises a layer of polyester, polyethylene, polypropylene, PVC, polyurethane, polyamide, rubber, elastomer, silicone, polystyrene, or cellulose foam in expanded form, woven or nonwoven.

 According to other aspects of the invention, an application of the insulating sheet to the production of a thermally insulating glove is proposed to the production of sheets, draw sheets or covers, for thermally insulating cushions, mattresses or water beds, and with a professional maintenance aid, along with the temperatures applied in cryotherapy or thermotherapy.

 The invent ion also proposes an advantageous device for protecting the phrenic nerve which is intended for use in cardiovascular surgery, said protective device comprising two parts of substantially oval shape, connected to each other by a constriction so that the two aforementioned parts substantially form an 8, said throttle defining, on the side of 8, a notch and comprising, on the opposite side, a finger comprising on its surface an adhesive strip, the two parts forming an 8 being ib ib th direction nt foldable one towards 1 further, my ni re re to define, after folding the adhesive strip of the finger on a fixing support fixed on the face of one of the two parts, opposite the adhesive strip, and extending substantially perpendicular to this adhesive strip, an envelope for the heart of a patient, said envelope being placed to isolate the heart from the phrenic nerve of the patient .

The two adhesive strips, which cooperate in order to give the protector of the phrenic nerve a pocket shape intended to receive the heart, can be replaced by a lace of fabric. Tighten the two lace strips, we form
(commuted with the purse strings) a pocket identical to
the one previously described.

Other features and benefits of
the invention will become more apparent from the description which goes
to follow.

In the accompanying drawings given by way of examples not
limiting:
Figure I is a section of an insulating sheet
according to the invention,
Figures 2 and 3 are time diagrams
which show the influence of the leaf conforms to
invention on the evolution of the temperature of the parts of the
patient's body on which this sheet is placed
artwork,
Figures 4 and 5 are plan views of the available
protective sitive according to the invention,
FIG. 6 is a perspective view of the protective device according to the invention, and
Figure 7 is also a flat view of a
variant of the protective device of Figures 4 to 6, of which
the pocket formatting means have been replaced by
a lace performing the same function when exercising a
pull on this lace.

In the example shown in Figure 1, the sheet
the thermally insulating 1 according to the invention comprises
a first thermally insulating layer 4 against which
is fixed, by any suitable means such as gluing or
heat sealing, a thermally reflecting layer 2.

Against this reflective layer 2, a second is fixed
thermally insulating layer 3 which is coated with a sheet of fabric 5, the outer surface of which is intended to
come into contact with a part of the patient's body, is to
preferably shaped to provide an anti-slip effect.

Of course, the insulating sheet conforms to
the invention may comprise several thermally reflective layers 2 and several thermally insulating layers 3, 4, each thermally reflective layer being between two adjacent thermally insulating layers.

 The reflective central layer is composed of shiny aluminum, preferably in the form of a complex of plastic and aluminum or metallized plastic, or alternatively of plastic in which a shiny shade has been incorporated in the form of a filler. In all three cases, perfect reflectivity of the calories is obtained. The best material is a plastic sheet.

preferably vacuum metallized polyester with aluminum.

 As already indicated, the reflective central layer 2 has an air space on its two faces. According to the invention, these air knives are produced by sheets of insulating material such as cellular foam of polystyrene or a low density material such as nonwovens, cellulose. fabrics, etc. ...

 The best way to obtain a 1 air core, that is to say an insulating layer avoiding direct contact of the human body with the reflective layer 2, is the use of a polyethylene foam. , polyethylene having the best permeability to infrared rays, that is to say to the heat of the human body.

 Using a polyethylene foam with a thickness equal to 2mm, on one side, an aluminum metallized polyester sheet with a thickness equal to 12 microns and a polyethylene foam sheet with a thickness equal to 3mm, on the side opposite, said metallized sheet being sandwiched between the two sheets of polyethylene foam, a radiation in heat reflection is obtained which is substantially between 80 and 90%. In practice, this means that the temperature of a member or part of the human body in contact with the insulating sheet I, itself in contact with a cushion of water, drops only by 1 to 20C, while this temperature, in the absence of the insulating sheet, would drop from 7 to 80C, causing a very unpleasant sensation for the patient (see time diagram in Figure 2).

 A particularly advantageous application of the invention is the use of the insulating sheet .1 in cardiovascular surgery, in particular during operations with an open heart, for the protection of the phrenic nerve which must in this case be thermally isolated from the heart.

Thanks to the use of the insulating sheet I, shaped in a manner which will be described later, the temperature of the phrenic nerve is maintained at substantially 300C w 20C for about I hour (see time diagram in Figure 3).

 The invention proposes for this purpose (see FIGS. 4 to 6) a protective device 10 comprising two parts 11, i2 of substantially oval shape, connected together by a throttle 15 so that the two parts 11, 12 substantially form an 8. Said constriction 15 defines, on one side of the 8, a notch 16 and comprises, on the side opposite to said notch 16, a finger 13 having on its surface an adhesive strip 14. The two parts 11 and 12 forming an 8 are substantially foldable towards each other, so as to define, after folding the adhesive strip 14 of the finger 13 on a fixing support 17 fixed on the face of the part 12, opposite the adhesive strip 14, and extending substantially perpendicular to this adhesive strip 14 (see in particular Figure 5), an envelope for the heart of a patient which is shown in perspective in Figure 6, said envelope being put in place, during an open heart operation, for iso the heart of the patient's phrenic nerve.

 When using the protective device 10, it is interposed between the phrenic nerve and the heart, so that the heart is placed in the hollow formed by the two parts 11 and 12 which are substantially folded back towards each other and maintained in this position by the fixing means 14 and 17, while the arteries leaving from and arriving at the heart are guided in the notch 16.

 The core itself, having been cooled to around 60C, remains at this temperature and does not heat up thanks to the thermal insulation action of the object of the present invention.

 The variant of protective device 10 'shown flat in Figure 7 is distinguished from the protective device 10 of Figures 4 to 6 only by the fact that the fastening means 14 and 17 have been replaced by a lace, for example fabric . In FIGS. 4 to 6, the adhesive strip 14 and the fixing support 17 can be, for example, two self-adhesive strips with an adhesive coating that is acronym for pressure, or two strips, one of which is provided with a multitude of small hooks which cooperate with a multitude of small loops with which the other strip is provided, and of the type marketed under the brand name of "VELCRO".

 In Figure 7, the lace 18 is folded over itself substantially in its central part so as to form two strands or bands 19 and 20 of substantially equal length, and its central part is against the internal face (relative to the shaped pocket ) of one 11 ′ of the two substantially oval parts Il ′ and 12 ′ to be folded back towards each other to form the pocket, and the two strands 19 and 20 of the lace 18 pass through slots 21 and 22 formed in this part it 's to extend against the external face of this same part 1 i', then not feels from the inside towards the outside in slots 23 and 24 formed in the finger 13 'and extend on the external face on the other oval part 12 'so that by pulling on the strands 19 and 20 of the lace 18. as on the beads of a purse, the parts e and 12' fold back towards each other in forming the receiving pocket of the heart. It then suffices to tie the two strands 19 and 20, after having formed with them a loop around the two parts ll ′ and 12 ′, folded down one substantially at 900 relative to the other, so that the pocket form automatically taken by the protective device 10 'is kept.

 The present invention can also be applied in surgery, cryotherapy or thermotherapy. Whenever a part of the human body is to be warmed or cooled, a prolonged action can be obtained by using the insulating sheet 1 according to the invention, and whenever a part of the body of a patient is not to be neither heated nor cooled, it is also possible to use this insulating sheet 1 for the purpose of separating said part of the surrounding region which is at a different temperature.

 The reference signs inserted after the technical features mentioned in the claims are intended only to facilitate understanding of the latter. and in no way limit its scope.

Claims (10)

 1. Thermally insulating sheet for use in the fields of orthopedics, medicine and surgery, characterized in that it comprises at least one thermally reflective layer (2) and at least one thermally insulating layer (3, 4 ) attached to the aforementioned thermally reflecting layer (2).  2. Insulating sheet according to claim I, ca characterized in that it comprises several thermally reflective layers (2) and several thermally insulating layers (3, 4), each thermally reflective layer being between two adjacent thermally insulating layers.  3. Insulating sheet according to one of claims l or 2, characterized in that one of the outer thermally insulating layers is coated with a sheet of fabric (5).  4. Insulating sheet according to claim 3 characterized in that the outer face of the fabric sheet (5) is shaped to provide an anti-slip effect.  5. Insulating sheet according to one of claims 1 to 4, characterized in that each thermally reflecting layer (2) comprises a polyester metal sheet - vacuum-coated, an aluminum sheet, or an aluminum paint or varnish.  6. Insulating sheet according to one of the preceding claims, characterized in that each thermally insulating layer (3, 4) comprises a layer of polyethylene, polypropylene, PVC, polyurethane, polyester, polyamide rubber, elastomer, silicone, polystyrene foam. , or cellulose in expanded form, woven or nonwoven.  7. Application of the insulating sheet according to one of the preceding claims to the production of a thermally insulating glove.  8. Application of the insulating sheet according to one of claims ì to 6 to the production of sheets, quilts or covers to insulate t he rmi queme n t cushions, mattresses or water beds.  9. Application of the insulating sheet according to one of claims 1 to 6 with the aid of the prolonged maintenance of the temperatures applied in cryotherapy or thermotherapy.  10. Application of the insulating sheet according to one of claims 1 to 6 to the production of a phrenic nerve protective device, intended for use in cardiovascular surgery, this protective device (10) comprising two parts (11, 12) in the sense of an ib oval shape, connected together by a throttle (15) so that the two parts (ll, 12) substantially form an 8, said throttle (15) defining, on one side of the 8, a notch (16) and comprising, on the opposite side, a finger (13) comprising on its face a strip, adhesive (14) or other matching fixing means, the two parts (11, 12) forming an 8 being substantially foldable towards each other, so as to define, after folding the adhesive strip (14) of the finger (13) on a fixing support (17) fixed on the face of the part (12), opposite the strip adhesive (14), and extending substantially perpendicular to this adhesive strip (14), one in Velcro for the heart of a patient, said envelope being placed to isolate the heart from the phrenic nerve of the patient, said envelope being placed to isolate the heart from the phrenic nerve of the patient during the operation.